During ageing, a decline in episodic memory is observed, characterized by decreased recollection (a). In this study, we investigated the influence of encoding instructions, intentional or incidental, on ... [more ▼]

During ageing, a decline in episodic memory is observed, characterized by decreased recollection (a). In this study, we investigated the influence of encoding instructions, intentional or incidental, on the performance of younger and older adults during an episodic memory task. Twenty young volunteers (aged 18 to 30 years old) and 20 older volunteers (aged 61 to 72 years old) participated in this experiment. The stimuli consisted of 300 black-and-white drawings of common objects. The task comprised two steps. During the encoding phase, 100 items were presented once ("hard" condition) and 100 other items were presented twice ("easy" condition). During recognition, the items from the encoding phase were presented again, as well as 100 new items. In each age group, half of the participants received incidental encoding instructions (they had to make size judgements about the objects depicted) while the other half were explicitly asked to memorize the objects presented because they would be asked to recognize them later on (intentional encoding). During recognition, they performed a Remember-Know judgement for the items they believed they had seen earlier. We carried out ANOVAs in order to test for the influence of instructions, age group and number of repetitions of the items in one hand on the percentage of recollection and on the other hand on the percentage of familiarity (p<.05). Results show a significant effect of age, with more correct recollection responses in young adults, whereas more correct familiarity was found in older adults. Furthermore, it was found that the items presented twice lead to more recollection than those presented only once. Finally, these results also suggest that in the older group of participants, only for the items presented twice, intentional encoding instructions lead to more recollection and less familiarity. This finding is consistent with previous work showing that the elderly do not easily use elaborate encoding strategies, and that they need more support (here, a second exposition to the material) in order to perform a deep encoding when they are encouraged to do so with intentional learning instructions (b). (a) Bugaiska, A., Clarys, D., Jarry, C., Taconnat, L., Tapia, G., Vanneste, S., & Isingrini, M. (2007). The effect of aging in recollective experience: the processing speed and executive functioning hypothesis. Consciousness and Cognition, 16(4), 797-808. doi: 10.1016/j.concog.2006.11.007 (b) Froger, C., Bouazzaoui, B., Isingrini, M., & Taconnat, L. (2012). Study time allocation deficit of older adults: the role of environmental support at encoding? Psychology and Aging, 27(3), 577-588. doi:10.1037/a0026358 [less ▲]

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear ... [more ▼]

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear to recruit prefrontal areas bilaterally when their encoding is successful, while in young adults this activation is found to be left-lateralized (b). In this study, we were interested in the differences between younger and older participant regarding cerebral activity during encoding depending on whether the item elicited recollection or familiarity during the recognition phase. Twenty young volunteers (aged 19 to 29 years old) and 19 older volunteers (aged 60 to 78 years old) were presented visual stimuli depicting objects. During a first fMRI session, they were asked to make a size judgement about them. Then, in a second phase, the subjects were shown the items previously encountered during the encoding phase, as well as distractors. Participants' task was to determine which one were new and which one were seen earlier. For the latter, they also performed a Remember-Know judgement. Data were analysed using SPM8, with an event design comparing modifications in cerebral activity between the two subjects groups during encoding (1) for the items leading to recollection during the recognition phase compared to those leading to familiarity, and (2) for the items associated with familiarity during the recognition phase compared to those which were not recognized. Results show that older adults display a heightened activity in the right middle frontal gyrus, medial cingulate and paracingulate left gyri as well as in the precuneus, bilaterally when they engage recollection processes. Given that activations in these areas did not correlate with performance, they could be interepreted either as dedifferentiation or as an attempt of the ageing brain to compensate for a less elaborate encoding. However, no increase of activity was associated with familiarity processes in older adults, possibly because they are less demanding regarding attentional resources. (a) Bugaiska, A., Clarys, D., Jarry, C., Taconnat, L., Tapia, G., Vanneste, S., & Isingrini, M. (2007). The effect of aging in recollective experience: the processing speed and executive functioning hypothesis. Consciousness and Cognition, 16(4), 797-808. doi: 10.1016/j.concog.2006.11.007 (b) Duverne, S., Motamedinia, S., & Rugg, M. D. (2009). The relationship between aging, performance, and the neural correlates of successful memory encoding. Cerebral Cortex, 19(3), 733-744. doi:10.1093/cercor/bhn122 [less ▲]

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear ... [more ▼]

It is now commonly accepted that a decline in episodic memory is observed with ageing: while recollection processes are impaired, familiarity seems to be relatively preserved (a). Older individuals appear to recruit prefrontal areas bilaterally when their encoding is successful, while in young adults this activation is found to be left-lateralized (b). In this study, we were interested in the differences between younger and older participant regarding cerebral activity during encoding depending on whether the item elicited recollection or familiarity during the recognition phase. Twenty young volunteers (aged 19 to 29 years old) and 19 older volunteers (aged 60 to 78 years old) were presented visual stimuli depicting objects. During a first fMRI session, they were asked to make a size judgement about them. Then, in a second phase, the subjects were shown the items previously encountered during the encoding phase, as well as distractors. Participants' task was to determine which one were new and which one were seen earlier. For the latter, they also performed a Remember-Know judgement. Data were analysed using SPM8, with an event design comparing modifications in cerebral activity between the two subjects groups during encoding (1) for the items leading to recollection during the recognition phase compared to those leading to familiarity, and (2) for the items associated with familiarity during the recognition phase compared to those which were not recognized. Results show that older adults display a heightened activity in the right middle frontal gyrus, medial cingulate and paracingulate left gyri as well as in the precuneus, bilaterally when they engage recollection processes. Amongst those regions, the precuneus seems to underlie compensatory processes, allowing the elderly to perform a richer encoding, as it was previously suggested for recollection processes during recall (c). However, no increase in activity was associated with familiarity processes in older adults, possibly because they are less demanding regarding attentional resources. (a) Bugaiska, A., Clarys, D., Jarry, C., Taconnat, L., Tapia, G., Vanneste, S., & Isingrini, M. (2007). The effect of aging in recollective experience: the processing speed and executive functioning hypothesis. Consciousness and Cognition, 16(4), 797-808. doi: 10.1016/j.concog.2006.11.007 (b) Duverne, S., Motamedinia, S., & Rugg, M. D. (2009). The relationship between aging, performance, and the neural correlates of successful memory encoding. Cerebral Cortex, 19(3), 733-744. doi:10.1093/cercor/bhn122 (c) Angel, L., Bastin, C., Genon, S., Balteau, E., Phillips, C., Luxen, A., . . . Collette, F. (2013). Differential effects of aging on the neural correlates of recollection and familiarity. Cortex, 49(6), 1585-1597. doi:10.1016/j.cortex.2012.10.002 [less ▲]